Multiple-speed axle



sept- 28, 1948. F. w. AVILA MULTIPLE-SPEED XLE Filed M1916/ 194s @d/a, y fau/CP.

Patented Sept. 28, 1948 MULTIPLE-SPEED Axim:

Frank W. Avila, Fort Wayne, Ind., asslgnor to International Harvester Company, a corporation oi' New Jersey Application August 16, 1943, Serial No. 498,799

3 Claims. (Cl. i4-314) This invention relates to a new and improved multiple speed axle. More particularly, the multiple, speed axle is obtained from a differential separate from the customary transmission.

Ordinarily, vehicles of the self-propelled type employ a transmission and 'a differential, and it has been the custom to obtain variable speeds for the vehicle by shifting of gears within the transmission and to utilize the differential only for the purpose of transmitting rotary motion at right angles to the source coming from the transmission.

It is, therefore, an important object of the present invention to continue to employ the regular transmission and in addition to provide gearing associated with a differential capable of causing further changes in vehicle speed so that the maximfum number of vehicle speeds obtainable is the product of the maximum transmission speed changes and the maximum differential speed changes.

Another important object of this invention is to provide a differential or nal drive for vehicles, particularly of the truck or tractor type, which is capable of a plurality of speed changes.

Another and still further important object of this invention is the provision of a differential having the customary direct drive between the transmission and the vehicle axles and also being capable of a Ilower speed under-drive and a higher speed over-drive.

Other and further important objects of the present invention will become apparent from the disclosures in the following specication and drawing, which shows a horizontal sectional view of the new and improved three-speed axle.

As shown in the drawing, the reference numeral II indicates generally a housing which contains the axle-shafts I2 and I3 adapted to be driven? A transmission, not shown, supplies a shaft I4 with any one of several possible forward and reverse speeds. The shaft I4 is journaled in the housing Il of the differential within roller bearings I6 and I1. The rear end of the shaft I4 terminates in a bevel pinion gear I8 adapted to drive a large bevel gear I9. A small stub shaft 2I extends rearwardly from and is integral with the pinion I8 and is journally guided within a bearing 22.

The driven bevel gear I9 is substantially in the form of a ring gear, inasmuch as it has no central hub. A ring 23 is equipped with internal clutch teeth 24 and external gear teeth 26, re-

spectively. This ring 23 has an outwardly extending annular flange member 21, which is fastened by bolts 28,v or other` suitable means, to the bevel driven gear I9. A second ring gear 29 is provided with internal gear teeth 3i and, with the aid of a lateral extension 32 and an outwardly extending annular flange 33, this ring gear is also ffastened to the gear I9 by means of the bolts 28 or the like. It will be evident, therefore, that asmotion is imparted to the bevel pinion I8 and thus to the bevel gear I9, the rings 23 and 29 will rotate as a unit.

The device as shown in the drawing is in neutral position so that there is no driving connection between the ring gears 23 and/or 29 with the vehicle laxle shafts I2 and I3.

The differential proper consists of beveled gears 34 and 36 splined to the centrally located ends o'f the vehicle axle shafts I2 and I3, respectively. These beveled gears 34 and 36 are joined by bevel pinions 31v and 38 at diametricallly opposite positions across the axle shafts I2 and I3. Each' of the pinions 31 and 38 has a stub shaft 39 and 4I, respectively, which are afilxed to the immediate differential housing 42. Roller bearings 43f,and 44 are positioned in annular recesses in the periphery of the housing 42 Iand Journally support the ring gears 23 and 29, respectively.

'I'he housing 42 of the differential proper comprises laterally extending tubular portions 46 and 4l, which respectively superimpose the axle shafts I2 and I3. A concentric ring 48 is splinecl to the periphery of the differential housing tubular portion 48, as shown at 49. This spline permits lateral sliding of the ring 48 along the length of `the housing portion 46 but imparts simultaneous rotation of the elements 46 and 48. External clutch teeth 5I are provided on the inner and end portion of the ring 48. The clutch teeth 5I form a concentric clutch member about the axis of the shaft I2. The ring 48 is affixed by threaded engagement, or any other suitable means such as welding, 'at 52 with a second, ring 53 coextensive therewith. The ring 53 has an annular external groove 54, which is adapted to be engaged by a fork-like member 56. which, upon being shifted on its upper slide shaft 51 by means of an actuator arm 58 engaging a notch 59 in a tubular extension 6I of the fork member 56, causes a sliding of the ring 46 and the now integral ring 53 on the spline 49 of the housing portion 46.

The actuator arm.58 is controlled by rocking of a sha-ft 62, which is preferably controlled from a station adjacent the drivers compartment of the vehicle. f

It will be seen, therefore, that a shifting of the gears.

actuator arm 68 in a leftward or counter-clockwise direction, as viewed in the drawing, will cause a leftward shifting off the ring 48 and result in engagement of the dental clutch gear 6I with the member 24. The engagement of teeth 24 and 6I creates a direct drive between the transmission-driven pinion gear I8 and the axles I2 and I8 inasmuch as the teeth 24 directly drive the teeth I which is an integral part of the ring 46. The fact that the ring 48 is splinedto the extended housing 46 of the dierential proper causes this housing 46 to rotate, and as the housing 46 and thus the housing 42 rotate, the beveled pinion gears 61 are rotated and cause the beveled gears 34 and 36 to be driven.

An eccentric bearing 63 superposes a portion of the ring 48, and by means of a bolt 64, or any other means, engaging a' lateral extension 66 in the relatively wide portion of the eccentric bearing 63, it is thus prevented from rotating. The bolt 64 is anchored to an arm 61, which is parallel with the fork member 66 and likewise slidably engages the upper shaft 61. The second ring 63 is provided with an outwardly extending an nular portion 68, which is turned inwardly to form a laterally extending flange 66. This laterally extending flange 66 has an internal ring gear 1I, which is concentric about the axis of the shaft I2. An eccentrically positioned ring 12 rides on the outer periphery of the bearing 63 and is equipped with external and internal ring gears 13 and 14, respectively, and constitutes double eccentric The external ring gear 13 is adapted to continuously engage the internal ring gear 1I at an upper portion thereof. As shown in the drawing, the ring gears 1I, 13, and 14 are motionless because the device is in a neutral position and not driving. When the device is shifted to a direct driving position-that is, when the dental clutchv teeth 24 and 6| are meshed-it will be evident that eccentric and concentric ring gears 1|, 16, and 14 rotate by reason of the fact that the ring 63 is rotatable with the ring 46 and hence drives through the flange 66 and gears' 1I to the ring 12. However, the drive at this point ceasesv and no harm is occasioned by these gears in rotative operation. However. when the shifting actuator arm 56 is moved in a rightward or clockwise direction, as viewed in the drawing, the external spur gear 26 will mesh with the internal ring gear 14 of the ring 12 at a lower portion thereof. The engagement of the gears 26 and 14 takes place after disengagement of the clutch teeth 24 and 6I and hence the ring 46 is now not directly driven but indirectlyV driven through the 'underdrive of ring gears 26, 14. 13, and thus 1I. The resultant drive of the axle shafts I2 and I3 is at a reduced speed and capable of supplying more power in driving of the vehicle.

On the right side of the housing II, and superposing the differential housing extension 41, is an eccentric bearing 16, and, similarly to the eccentric bearing 63, this bearing 16 is held non-rotatable by means of its attachment to the anchor ann 11. Superposing this bearing 16 is a ring 18 having external and internal gear teeth 16 and 8|, respectively. The ring 18 is provided with an annular groove 82, such as lthe groove 64 on the left-hand side of the device. anis engaged by a fork-like member 83 which is siidabie on a shaft 64 journaled in the housing I I of the entire differential unit. A second actuator arm 86 is adapted to be rotated about a shaft 81, which likewise with the shaft 62 is preferably operable from a position adjacent the driver of the vehicle.

4 The end of the actuator arm 86 engages a notch 86 in a slidable bearing member 86 which is integral with the fork member 63 and the bearing anchor member 11. As shown in the drawing. the actuator arm 66 is shown in a neutral position, wherein no gears are meshing. Upon a leftward shifting of this actuator arm 86, the fork member 63 causes the external gear 16 to mesh with the internal concentric ring gear 3|. Inasmuch as the bearing16 is eccentric and the ring 16 superposes this eccentric bearing, the ring itself will be eccentricaliy positioned with respect to the axis vof the shaft I3. Therefore, engagement of gears 3| and 16 takes place only over a portion a/t the upper side thereof, such as is the case'for the left side gearing, namely: the gears 1I and 13. It will be seen that herein is provided an eccentric overdrive through the gears 3|, 19, 6I, and a gear 6I formed integrally with the sleeve-type housing 41 of the differential proper. The gear 6I projects sufficiently far to the right as shown in the drawing so that even when the gears 3| and 16i are not engaged but are in a neutral position, as shown, the gear 6| overlaps as shown at 82 with the gear 8| and causes a continual drivingof the ring 16. This continual meshing of the gears 8| and 6I is conducive to synchronous meshing of the gears when it is desired to engage the gears 3l and 16.

Inasmuch as this last-explained drive is an overdrive, it will be evident that the speed of the transmission driven shaft I4 is increased before it is transmitted to the axles l2 and I3. and hence in combination with the first-described drives the differential is capable oi' direct under-drive and over-drive. If, as is customary in trucks or the like, the transmission 'is supplied with four forward speeds and one reverse speed, it is obvious that the number of forward speeds has been increased to twelve and the number of reverse speeds has been increased to three. The advantages of such a device are quite numerous and certainly a driver with so many closely spaced gear ratios can maintain the maximum road speed consistent with engine power.

In order to more adequately support and balance the differential proper and the eccentric and concentric ring gears, bearings 86 and 64 iournally support the ends oi the extensions 46 and 41 of the differential housing 42 within the main housing I I. A further feature which is conducive to balancing of the entire differential and the gear-changing mechanism, is the fact that the gear changes are split up and positioned on both sides of the differential proper; that is, the direct and under-drive gearing are positioned to the left of the differential proper and the over-drive is positioned to the right of the differential proper, but, of course. the gearing shown may be interchanged as desired.

An interlock is preferably provided between the operation of shafts 62 and 81 so that when one set of gears is engaged, the other set must necessarily remain in neutral. This prevents a clashing of gears and an attempt to drive the differential at two speeds which certainly would prove fatal to the device. The interlock between the shafts 62 and 81, or between the actuator arms 68 and 86,

Various modifications may be incorporated in this device without departing from the principles disclosed herein, and I, therefore, do not propose limiting the patent granted hereon otherwise than as necessitated by the appended claims."

In the claims:

1. A combined differential and change speed unit having axially aligned axles and axle driving gears mounted thereon and bevelled pinion gears in driving engagement with said axle driving gears comprising a driving member having a lateral extension to one side of said diil'erential, a driven member concentric with said axially aligned axles and. carrying said beveled pinion gears. a multispeed gearing adjacent said differential, said multispeed gearing including a laterally shiitable member carrying an internal ring gear and a laterally spaced external dental clutch member, said shiitable member arranged and constructed to rotate concentrically with said driven member, an external ring gear carried on said lateral extension and an internal dental clutch member forming part of said lateral extension said external ring gear-and the internal dental clutch positioned intermediate the internal ring gear and the rlaterally spaced external dental clutch member, and a ring membexfeccnmcauy iournalemwitnln said laterally shlftabie member, said ring member having anexternal ring gear andan internal ring gear, the external ring gear 0f the eccentrlcally Journaled member being in cooperative engagement with the internal ring gear of the laterallahiftable member,

6 direction will eifect a direct drive through the cooperative external and internal dental clutch members. 2. A dlilerential and change speed unit as set -forth in claim 1 in which the driven member comprises a sleeve lournaled on said axially aligned ber mounted for rotation on said axially shittable whereby lateral shifting movement o! the shlttcircular member and for axially shiftable movement with said member, said driven vmember having an external gear formed thereon concentric with id axles. said annular member having an ext al ring gear engageable with said internal ring gear on said second lateral extension upon sluiting of said annular member, and an internal ring gear on said annular member simultaneously engageable with the external gear formed on the driven member for effecting an overdrive.

FRANK W. AVILA.

REFERENCES CITED 'f The following references are of record in the ille of this patent:

. STA'I'ES PATENTS Number l 

